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    <title>Document</title>
    <script src="https://cdn.bootcdn.net/ajax/libs/lodash.js/4.17.21/lodash.min.js"></script>
    <style>
        ul{
            width: 300px;
        }
        li{
            height: 40px;
            border-bottom: 1px solid #000;
        }
    </style>
</head>
<body>
    <div>
        <ul>
            <li>1</li>
            <li>1</li>
            <li>1</li>
            <li>1</li>
            <li>1</li>
            <li>1</li>
            <li>1</li>
            <li>1</li>
        </ul>
    </div>
    <script>
        const oLis =document.querySelectorAll("ul li")
        function enter() {
            console.log(1);
            this.style.background="red";
        }
        function leave(){
            console.log(2);
            this.style.background="";
        }
        const throttleEnter=_.throttle(enter,30,{
            trailing:false,
            leading:true,
        })
        const throttleLeave=leave;
        oLis.forEach((item) =>{
            item.onmouseenter=throttleEnter;
            item.onmouseleave=throttleLeave;
        })
    </script>
    
</body>
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